As any of you will know who have played with Exchange or OCS 2007 you need to get your certificates right when you start!
This invariably means the use of a certificate with Subject Alternative Names (SAN). Until recently there have been on three places to purchase these online, and whilst you could create your own that caused the usual trusted root problems.
So you will be pleased to know that GoDaddy, one of the better cheap certificate providers has now started providing these certs!
Take a look here for more info: